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Chemistry!?. Chemistry 121.08 Fall 2013. Dr. Azizeh Farajallah Office: IB 2324C Phone number: 934-3940 Email: azizeh.farajallah@seattlecolleges.edu Office hours : W/Th 5-5:50pm . Chapters 1-10. Grading?. Exams : two 1hr exams (100pts each), cumulative final exam (150pts)
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Chemistry 121.08 Fall 2013 Dr. Azizeh Farajallah Office: IB 2324C Phone number: 934-3940 Email:azizeh.farajallah@seattlecolleges.edu Office hours: W/Th 5-5:50pm Chapters 1-10
Grading? Exams: two 1hr exams (100pts each), cumulative final exam (150pts) Lab: 7 & 25pts each (lowest dropped). No make up lab and if missed more than one lab you receive 0.0 for the course Lab continue: I will discuss safety and lab policies in details later Worksheets: 8 & 20 pts each (lowest dropped). No make up. Instructor Evaluation: Your conduct in lecture (being on time) and lab (safety, notebook, cleaning)
Grading? • Extra Credit: occasional extra questions on exams • Attendance: for lecture, during the first week for lab, attendance is taken for every lab. Missed lectures or lab? • Responsibility: You are responsible for everything covered in lecture and assigned from the book. • Waiting List: Depending on first week attendance and drop out rate?
Grading? Rough Grading Scale: 100 – 95 % 4.0 90 % 3.5 70% 1.5 85 % 3.0 65 % 1.0 80% 2.5 60 - 62% 0.7 75% 2.0 <60 % 0.0 <55% 0.0
Night class challenges! • Please come a wake and plan to stay a wake • 4 hours night class will be a challenge no matter what!
Chemistry 121.08 Fall 2013 Mondays: ecture 6:00-8:20 pm with break Worksheet: 8:20-9:20pm Wednesday: Lecture 6:00-8:00 pm with a break Lab: 8:00-9:20pm
How to succeed in this course? • Attend lectures (seek help if you miss a lecture) • Practice end of chapters HW • Don’t miss any of the worksheets or labs • Submit reports and prelabs on time • Form a study group
Chemistry around us! p. 4
What is chemistry? Chemistry is the study of matter
Chapter 1 Matter and Measurements
Matter? • Matter is every thing around you, it is anything that has mass and occupies space (volume).
Matter & Mass • Mass is a measurement of the amount of matter in an object. • Mass is independent of the location of an object. • An object on the earth has the same mass as the same object on the moonwhich is different than weight!
Air, water, smoke, and light? Mass? Occupies space? water? smoke? Air? You can trap smoke in a bottle Mass and occupies space Air trapped in a balloon makes it heavier O2, CO2, N2 and so on which has mass
Smoke and light? Smoke is made up of carbon, water vapor and gases. Light is made up of photons that are massless and doesn’t occupy space.
Matter • Matter can be: • Synthetic (human-made): • nylon • Styrofoam • ibuprofen • Naturally occurring: • cotton • sand • digoxin, a cardiac drug
Solid, liquid and gas • A solid has a definite shape and volume. • Aliquid has a definite volume but it takes the shape of a container whereas • agas fills the entire volume of a container.
States of matter • Plasma: Heating gas may ionize its molecules or atoms (reducing or increasing the number of electronsin them), thus turning it into a plasma, which contains charged particles: positive ions and negative electrons or ions. Example: Our sun and all of the stars.
Properties of matter? Physical and Chemical Properties • Physical property is a property that can be observed or measured without changing the identity of that matter • Examples: color, odor, shape, mass ect
Chemical property • Chemical property is a property that can be observed or measured only by changing the identity of matter into a new substance. • Examples: flammability and the ability to react (e.g. when vinegar and baking soda are mixed)
Physical changes • Take place without changing the identity of matter. • Examples: freezing, melting, or evaporation of a substance (e.g. water)
Chemical changes • Are always accompanied by a change in the identity of matter (composition). • Examples: burning of paper and the fizzing of a mixture of vinegar and baking soda
Chopping wood Physical Change? Chemical Change?
Log burning Physical Change? Chemical Change?
Frying eggs Physical Change? Chemical Change?
Which of the following is a physical change? {image} Which of the following is a physical change? • Food digesting breaking down particles (changing identity) chemical change • Sodium reacting with water (change identity) 2 Na + 2 H2O > 2 NaOH + H2
Which of the following is a physical change? {image} Which of the following is a physical change? • Methanol burning in air • (changing identity) • Chemical change • Caution methanol is very flammable • Liquid helium boiling • (no change in identity) • Physical change
Classification of matter • Now that we learned chemical and physical properties of matter, we can use that to help us classify it. • One way chemists classify matter is based on its purity.
Classification of matter Most pure Most impure
Classification of matter (continued) • Mixtures: • Two or more pure substances mixed together. • Each substance in the mixture retains its own set of chemical and physical properties and can be separated by physical means • Example: mixture of table sugar and water • how can we separate this mixture?
Physical separation of mixtures • How can you separate a mixture of iron, salt and sand • Remove iron with a magnet, then dissolve the rest in water, filter to separate sand and salt.
Classification of matter • Pure substance: • Pure substance can’t be broken down to other pure substances by any physical change. • Pure substances can also be divided into 2 categories: elements and compounds.
Pure substances: elements • Elements – Substances made up of only one type of atom. - Cannot be separated by any physical OR chemical process. Examples: Carbon Helium Gold
Pure substances • Compound – Two or more elements chemically bonded together. Examples: Carbon Dioxide (CO2) Water (H2O) Salt (NaCl) Sucrose (C12H22O11)
Measurements & units • Matter can be classified and some physical and chemical properties can be observed without measurements! • Measurements and calculations expand our ability to understand the chemical nature of the world around us. • Remember what Matter is (have mass and occupies space volume)
Measurements & units • Chemistry is largely a quantitative science! Theories and ideas are tested by measurements? Measurements are usually quantitative (have numbers) • Measurements consist of a number and an identifying unit • The number is meaningless without the unit 100ml 335.39g
Measurements & units • Measurements are important in health sciences as well.
Standards of the past • People used to use parts of their body to determine the length of something. • The standard would be a part of the king’s anatomy. • The standard yard was the distance from the king’s nose to his outstretched arm
People would use their feet to measure distance • This is how the term foot came about. • Today the standard “foot” in the English system is • 12 inches = 1 foot
Systems of measurements? The Old vs the New! • Old system What the US uses today arrived from England and is also known as the United States Customary Systems (USCS)
New System:System International (S.I) (the metric system) Systems of measurements? Each type of measurement has a baseunit in the metric system..
The metric system • Other units are related to the base unit by a power of 10. • The prefix of the unit name indicates if the unit is larger or smaller than the base unit.
Length: the meter? • The standard for the meter is kept in a safe in France. • The meter stick is a replica of that standard 1 kilometer (km) = 1,000 meters (m) 1 km = 1,000 m 1 millimeter (mm) = 0.001 meters (m) 1 mm = 0.001 m 1 centimeter (cm) = 0.01 meters (m) 1 cm = 0.01 m
Scientists needed a standard to measure mass. Mass is the amount of matter in an object They decided to take one cubic centimeter of water and call it a gram Mass: how the gram came about? 1 kilogram (kg) = 1,000 grams (g) 1 kg = 1,000 g 1 milligram (mg) = 0.001 grams (g) 1 mg = 0.001 g
Volume: how the liter came about? • Scientists needed a way to measure liquids so they took 10 cm and multiplied it by its length x width x height to come up with a standard for measuring volume
Measuring Volume 1 kiloliter (kL) = 1,000 liters (L) 1 kL = 1,000 L 1 milliliter (mL) = 0.001 liters (L) 1 mL = 0.001 L Volume = Length x Width x Height = cm x cm x cm = cm3 1 mL = 1 cm3 = 1 cc
The time standard • During the 15th century a scientist named Galileo set the standard of time known as the second
Measurements & Units • Measurements are made using measuring devices (e.g. rulers, balances, graduated cylinders, thermometer, etc.). Length (meter) Temperature (degree Celsius) Time (seconds) Volume (liter) Mass (grams)